in reply to Re: Defining an XS symbol in the Makefile.PL (quoting)
in thread Defining an XS symbol in the Makefile.PL

I don't quite follow, but I did try your suggestion of DEFINE => q{"-DMY_FORMAT=\"%.17\""} in the Makefile.PL.
Note that I've altered the .16e to .17, as that's what's needed by the module I'm actually testing.
That does allow the compilation to succeed and I do see this output during the build: 
gcc -c   -s -O2 -DWIN32 -DWIN64 -DCONSERVATIVE -DPERL_TEXTMODE_SCRIPTS
+ -DPERL_IMPLICIT_CONTEXT -DPERL_IMPLICIT_SYS -DUSE_PERLIO -D__USE_MIN
+GW_ANSI_STDIO -fwrapv -fno-strict-aliasing -mms-bitfields -s -O2   -D
+VERSION=\"1.52\" -DXS_VERSION=\"1.52\"  "-IC:\_64\perl530_810\lib\COR
+E"  -DPERL_EXT -DUSE_PPPORT_H "-DMY_FORMAT=\"%.17\"" ListUtil.c

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which, I think, looks right.
However, the XS code that relies on MY_FORMAT being set correctly still fails.
I therefore stuck the following in the XS code to see exactly what MY_FORMAT looks like: 
printf("\n**%s**\n", MY_FORMAT);

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And that prints out **.17**, showing quite clearly that the quotes && the percentage sign have been lost.

This Inline::C script also fails to build: 
use strict;
use warnings;
use Config;

use Inline C => Config =>
  USING => 'ParseRegExp',
  CCFLAGSEX => q["-DMY_FORMAT=\"%.16e\""],
  BUILD_NOISY => 1,
;

use Inline C =><<'EOC';

SV * foo(void) {
  printf(MY_FORMAT, sqrt(2.0));
  printf("\n");
}

EOC

foo();

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During the build I get: 
gcc -c  -iquote"C:/_32/C" -s -O2 -DWIN32 -DWIN64 -DCONSERVATIVE  -DPER
+L_TEXTMODE_SCRIPTS -DPERL_IMPLICIT_CONTEXT -DPERL_IMPLICIT_SYS -DUSE_
+PERLIO -D__USE_MINGW_ANSI_STDIO -fwrapv -fno-strict-aliasing -mms-bit
+fields "-DMY_FORMAT=\"%.16e\"" -s -O2   -DVERSION=\"0.00\" -DXS_VERSI
+ON=\"0.00\"  "-IC:\_64\perl530_810\lib\CORE"   try_pl_d937.c
<command-line>: warning: missing terminating " character
try_pl_d937.xs:1:10: fatal error: EXTERN.h: No such file or directory
 #include "EXTERN.h"
          ^~~~~~~~~~
compilation terminated.

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I am still quite open to testing other suggestions ... though I'm well and truly over trying to work it out for myself.

Cheers,
Rob

Replies are listed 'Best First'.
Re^3: Defining an XS symbol in the Makefile.PL (quoting)
by Anonymous Monk on Aug 19, 2019 at 08:41 UTC
    Um...so what did mycode show?
[reply]
      Um ... what code ?
[reply]

        Heh, whats going on? 

        #!/usr/bin/perl --
use strict;
use warnings;
use Config;

use Inline C => Config =>
  USING => 'ParseRegExp',
  CCFLAGSEX => q["-DMY_FORMAT=\"%.17e\""],
  BUILD_NOISY => 1,
  CLEAN_AFTER_BUILD => 0,
;

use Inline C =><<'EOC';

void* foo(void) {
    printf("***%s***\n", MY_FORMAT);
    printf(MY_FORMAT, sqrt(2.0));
    printf("\n%.17e\n", sqrt(2.0));
}

EOC

foo();

__END__
$ perl inline-eumm-define-sprintf-11104628.pl
validate Stage
Starting Build Preprocess Stage
get_maps Stage
Finished Build Preprocess Stage

Starting Build Parse Stage
Finished Build Parse Stage

Starting Build Glue 1 Stage
Finished Build Glue 1 Stage

Starting Build Glue 2 Stage
Finished Build Glue 2 Stage

Starting Build Glue 3 Stage
Finished Build Glue 3 Stage

Starting Build Compile Stage
  Starting "perl Makefile.PL" Stage
Generating a dmake-style Makefile
Writing Makefile for inline_eumm_define_sprintf_11104628_pl_5316
Writing MYMETA.yml and MYMETA.json
  Finished "perl Makefile.PL" Stage

  Starting "make" Stage
Running Mkbootstrap for inline_eumm_define_sprintf_11104628_pl_5316 ()
"D:\perl\bin\perl.exe" -MExtUtils::Command -e chmod -- 644 "inline_eum
+m_define_sprintf_11104628_pl_5316.bs"
"D:\perl\bin\perl.exe" -MExtUtils::Command::MM -e cp_nonempty -- inlin
+e_eumm_define_sprintf_11104628_pl_5316.
bs blib\arch\auto\inline_eumm_define_sprintf_11104628_pl_5316\inline_e
+umm_define_sprintf_11104628_pl_5316.bs 644
"D:\perl\bin\perl.exe" "D:\perl\site\lib\ExtUtils\xsubpp"  -typemap "D
+:\perl\lib\ExtUti
ls\typemap"  inline_eumm_define_sprintf_11104628_pl_5316.xs > inline_e
+umm_define_sprintf_11104628_pl_5316.xsc
"D:\perl\bin\perl.exe" -MExtUtils::Command -e mv -- inline_eumm_define
+_sprintf_11104628_pl_5316.xsc inline_eu
mm_define_sprintf_11104628_pl_5316.c
gcc -c           -s -O2 -DWIN32  -DPERL_RELOCATABLE_INCPUSH -DPERL_TEX
+TMODE_SCRIPTS -DUSE_SITECUSTOMIZE -
DPERL_IMPLICIT_CONTEXT -DPERL_IMPLICIT_SYS -fno-strict-aliasing -mms-b
+itfields -D_USE_32BIT_TIME_T "-DMY_FORMAT=\"%.17e\
"" -s -O2         -DVERSION=\"0.00\"    -DXS_VERSION=\"0.00\"  "-ID:\p
+erl\lib\CORE"   inline_eumm_define_spri
ntf_11104628_pl_5316.c
"D:\perl\bin\perl.exe" -MExtUtils::Mksymlists \
     -e "Mksymlists('NAME'=>\"inline_eumm_define_sprintf_11104628_pl_5
+316\", 'DLBASE' => 'inline_eumm_define_sprintf_111
04628_pl_5316', 'DL_FUNCS' => {  }, 'FUNCLIST' => [], 'IMPORTS' => {  
+}, 'DL_VARS' => []);"
g++ inline_eumm_define_sprintf_11104628_pl_5316.def -o blib\arch\auto\
+inline_eumm_define_sprintf_11104628_pl_5316\inline
_eumm_define_sprintf_11104628_pl_5316.dll -mdll -D_USE_32BIT_TIME_T -s
+ -L"D:\perl\lib\CORE" -L"D:\perl\mingw\mingw32\i686-w64-mingw32\lib" 
+inline_eumm_define_sprintf_11104628_pl_5316.o   "D:\perl\lib\CORE\li
bperl516.a" -lmoldname -lkernel32 -luser32 -lgdi32 -lwinspool -lcomdlg
+32 -ladvapi32 -lshell32 -lole32 -loleaut32 -lnetap
i32 -luuid -lws2_32 -lmpr -lwinmm -lversion -lodbc32 -lodbccp32 -lcomc
+tl32 -Wl,--enable-auto-image-base
"D:\perl\bin\perl.exe" -MExtUtils::Command -e chmod -- 755 blib\arch\a
+uto\inline_eumm_define_sprintf_11104628
_pl_5316\inline_eumm_define_sprintf_11104628_pl_5316.dll
  Finished "make" Stage

  Starting "make install" Stage
"D:\perl\bin\perl.exe" -MExtUtils::Command::MM -e cp_nonempty -- inlin
+e_eumm_define_sprintf_11104628_pl_5316.
bs blib\arch\auto\inline_eumm_define_sprintf_11104628_pl_5316\inline_e
+umm_define_sprintf_11104628_pl_5316.bs 644
Files found in blib\arch: installing files in blib\lib into architectu
+re dependent library tree
Installing _Inline\lib\auto\inline_eumm_define_sprintf_11104628_pl_531
+6\inline_eumm_define_sprintf_11104628_
pl_5316.dll
  Finished "make install" Stage

  Starting Cleaning Up Stage
  Finished Cleaning Up Stage

Finished Build Compile Stage

***%.17e***
1.41421356237309510e+000
1.41421356237309510e+000

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[d/l]

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